Your example doesn't look ugly, it's just something that ought to be saved for dialogue. I wouldn't use it in non-fiction, for example.
Another method is to italicize the word.
This example is way oversimplified.
Adding emphasis with italics can mean to say it slightly louder or clearer or even pause for the briefest of periods (too long for a comma or dash) before saying it. But the most common form of emphasis here would be to elongate the word.
This works very well for an example that is a single syllable where only the vowel can be elongated. The only way it could go is "waaaaay." For a different word, let's say "kissy," as in "kissy face," you wouldn't know if kissy was supposed to be said "kiiiiiiiissy" or "kisssssssssy" or "kisseeeeeeeeee." It may not matter though, as each reader can imagine it their own way.
If italics works in general but doesn't imply a long enough elongation, you can add that to your narration. Though that's often more awkward than it's worth.
So, is there punctuation that can indicate elongation? No. Not any that works for regular fiction anyway.
If describing it isn't the right approach, then formatting is your friend. Italics if that works. Or add in those extra letters, with spelling changes as needed.